Improvement in electric telegraphs for transmitting musical, tones



ZShee'ts SiheetI. E. EBAY. I Electric Telegraphiur Transmitting Musical Tones No.166,096. Patentediuly27,i875;

Y ijmmmwmmmnmmnwlmil WITNESSES v INVENTOR zsheexs sheet.

E. G RAY.

Elect ric Telegraph for Transmitting MusicalTones.

No. l66,096. PatentdJuly2 7,l87-5.

WITNESSES INVENTOR I UNITED STATES PATENT 'QFFICE.

' ELISl-IA GRAY, or CHICAGO, ILLINOIS, .AssIcNon 0F ONE-HALF insurance 'ro SAMUEL s, WHITE, on PHILADELPHIA, PENNSYLVANIA.

lMPROVEMENT IN ELECTRlC TELEGRAPHS FOR TRANSMITTING MUSICALLTONES.

Specification forming part of Letters Patent Nos] 66,096, dated July 27, L575; application tiled January 19, 1875. H

CASE 1.

To 'aZZ 'whom it may concern;

Be it known that I, ELISHA GRAY, of Chicago, in the county of- (Jook and State of Illinois, have invented a new and useful Art of Transmitting Musical Impressions or Sounds Telegraphically,as well as ccrtai n new and useful Improvements on Apparatus for so Transmitting such Impressions or Sounds; of which art and apparatus I hereby declare the following to be a full, clear, and'exact description.

My invention relates to a novel art of transmitting musical impressions or sounds telegraphically which impressions or sounds may be utilized as signals for the transmission of intelligence. I r

My invention is based upon the well-known law of acoustics that bodies vibrating with difierent rapidity produce tones of difl'erent pitch; and upon my own discovery that such vibrations can be transmitted through a telegraphic circuit and reproduced in a musical.

tone or note of a pitch corresponding with that originally transmitted, by including in the circuit animal tissue-or other equivalent substance, which will cause a slight resistance to the electrical current at the point of contact between such animal tissue and some resonant conductor of electricity. I lily-improvement consists in a new and useful art of producing musical impressions or sounds at the transmitting end of a telegraphic circuit, by causing interruptions in the electric currents of sufiicient frequency'to produce mu-' sical tones, transmitting said tones through an electric circuit composed in part of animal tissue,and reproducing them at the receiving end of the line by means of aresonant body,which is also a conductor of electricity. My improvement further consists. in a new and useful apparatus forcarrying out the objects of my invention; which apparatus con sists of the combination of a telegraphic circuit, composed in part of animal tissue ;'a circhit-breaker capable of producing a musical tone';, and a receiver capable of reproducing that tone at the receiving end of the circuit.

My improvementfurther consists of the combination, in an apparatus suclras described, of

-arcorresponding' key.

a series of circuit-breakers capable of produc ing musical tones of different pitch, and a series of keys for simultaneously or successively throwing the circuit-breakers into or out of operation,whereby several tones simultaneously or successively may be transmitted through a single wire. t

The subject-matter claimed will hereinafter specifically be designated.

In the accompanying drawings, Figure 1 represents a plan or top view of a portion of the transmitting apparatus, Fig. 2 is a frontelevation of the same, and Fig. 3 a diagram,

showing an arrangement of partsfand circuits which advantageously may be employed in working my invention.

The transmitting apparatus is mounted, as usual, ppon a base-board, A. An inductioncoil, B, is provided'with primary and secondary helices of the usual construction. A common vibrating electrotomc, 0, having its circuit-breaking spring a of such length, thickness, and adjustment that its vibration produces-a musical tone of a certain pitch,'forn1s part of the circuit.

It is obvious that the apparatus may be worked with asingle electrotome,the pitch of i which may be varied byadjustnient; but

where a series of tones of different pitch is desired, I prefer to employ a series of elect-r0- tomes having difl'erent rates of vibration.

Two electrotomes, O C, of identical construction but differing in pitch, are shown in the drawings, but I propose, under some elrcumstances, to use a series of electrotonies which will give tones extending through one or more octaves. These electrotomes are, by prefe'rencegplacedin the primary circuit of the induction-coil, and,when in operation, induce secondary currents or impulses in the secondary circuit of said coil equal in number to the vibrations of the circuit-breaking spring of the electrotome. v

An ordinary telegraph-key situated in the primary circuit opens or closes the connections of the battery. Each electrotome' must have In the drawings, two keys, D D, are shown, both of which, as well as the clectrot-oines, are situated in the primary circuit, which is divided or branched in order to pass through them. I

Fig; shows the arrangement of i the cir- 'cuits. The p'rimary'circuit 13 connected with the battery E passes through the keyes D D, the magnets of the electrotomes, and the primary-circuit of the induction-coil B. One terminal of the secondary circdit G extends from the inductioncoil to the receiving station through animal tissue to a suitable resonant conductor of electricity, which is; in this case,

a hollow mctallicveylinder, H, which is con- .nected with the ground; vthe other terminal, I,

and elastic; and of having a surface of greater electric resisting capacity than its interior.

These charactcristices are found in the skin of the human body; in leather moistened with acidulated water, in animal flesh covered with a membraneous coating; in bacon-rind in pork-skin, especially pieces taken from the ear or tail; in kid gloves; and in other substances which need not be enumerated, as they do not operate so perfectly as those above given,

The operation of the apparatus is as follows: The closing of either of the keys completes the primary circuit from the battery through the electroiome connected with the key depressed, and the circiiit-closing;spriiig ofsaid electrotonie will immediately be-thrQwn into rapid Vibration, and a musical tonevf a certain pitch dependent upon the length,

thickness, and adjustment of the spring will be given forth, while at each vibration the current in the primary circuit of the induction apparatus will be interrupted. These interruptionsproduce correspondingsecondarycurrents or impulses in the secondary circuit of' the induction apparatus, and these secondary induced currents or impulses are transmittedv to the receiving-station. Thus, for example, if the circuit-lneaking spring of the electrotome vibrates one hundred and twenty-eight times per second, the tone given forth is that known as the fundamental C, while one hundred and twenty-eight terminal secondary currents or impulses will be induced in the secondary circuitof the-induction apparatus, and transmitted through the animal tissue above mentioned, forming part of said circuit, to the resonant receiver, and will, from some cause not understood or cnplicable in the present stage of the art, vibrate the same synchronously with the transmitting-elcctrotomc, and thus give forth a musical tone of the same pitch.

above a sonndiug-boari'l, such, for instance, as

thebody of an ordinary violin, may be-iused with good effect to receive thevibrations, instead of the hollow eylinderabove described.

From the foregoing description it; will be seen that IQIiSiOfllUOllQS producedat the transmitting- 'stationcan simultaneously be produced at the receiving station however distant. When two or more keys are simultaneously or. successively depressed, corresponding tones will simultaneously be't-ransi'nitted, thus producing harmony or melody. V

The interruptions in the primary circuit, which cause theinducod secondary curreptsor impulses, may be produced by a mechanical circuit-breaker having the requisite rapidity of motion, such as a revolving wheel orrevolving brush; or they may be produced by providing the vibrating reed or reeds of an organ with contact-points, so that, as the reed vibrates, it will transmit impulses correspondingin number per second to the number of vibrations per second of the notes so'undedby the organpipe.

I prefer to use the impulses of the induced secondary currents as the transmitting medium, as suchvuse affords'the most convenient way of obtaining electricity of high tension, which is that best adaptedfor penetrating a slightly-resisting medium, such as. the animal tissue hereinbefore mentioned.

The secondary coil is not essential, as the secondary circuit induced in the primary coil may be utilized for transmitting the signals.

My improvement enables me to operate with a very slight amount of current, as the hat- I tery power required to produce and transmit the vibrations is less than one-hundredth part of the battery power now required to transmit signals over long land-lines.

My improved method can advantageously be substituted for the Morse telegraph-alpha bet now in general use, as an alphabet can be constructed on the principle of using tones of different pitch for the different letters, which will admit of great rapidity of transmission.

By means of my improycd apparatus not only may a tune be transmitted by a single operator toa distant point, but the different parts of, such tune simultaneouslyjmay be re produced ata common point from difierent places, a separate part of the tune being played at each place.

The apparatus can also advantageously be employed in studying acoustics and the phys-,

ical theory of music.

The combination, with a main line, of an in tcrmittent circuit-breaker, or a series thereof, each adapted to throw upon the line a definite number of electrical impulses per unit of time, and a key or kcys,'on e for, and controlling,

each such-circuit-breaker, are not broadly claimed herein, as they constitute apart of the subject-mattcr of another application for Letters Patent of the United States, .filed by me February 23, 1875.,

A metallic plate stretched by mctallicstrings I claim as my invention 1. The hercinbcfore-described art of transmitting musical impressions or sounds telegraphically, by producing musical impressions, or sounds at the transmitting ,end of a telegraphic circuit by causing interruptions in the electric currents of sufiicient frequency to produce musical tones,. transmitting said tones through an electric circuit composed in part of animal tissue, and reproducing them at the receiving end of the line by means of a resonant body, which is also a conductor of elecvtricity, substantially as set forth;

2. The electro'harmonic telegraph apparatus, hereinbefore set forth, consisting of the combination of a telegraph-circuit, composed- I in partof animal'tissue, a circuit-breaker capable of producing aniusical tone, and faresoceiver, which is also a conductor ofelectricity,

a series of circuit-breakers capable of producing musicaltones of difierent pitch, and a corresponding series of keys for throwing the circuit-breakers into'or out of operation, whereb'y'sgveral tones simultaneously may be trans mitted through a single wire.

- l ELISHA GRAY. Witnesses:

\VM. J. PEYTON, E. C(Dnvrnson. 

